Good looks translate to better grades in high school, but the super-attractive don't have an extra advantage in their GPAs, according to an analysis published this week and based on a national survey of almost 9,000 high school students.

Being the most beautiful or handsome is not as important as being above average, sociologist Rachel Gordon of the University of Illinois-Chicago suggests in a peer-reviewed book from the Society for Research in Child Development, which she co-authored.

For both girls and boys, being rated as attractive rather than average in looks — what Gordon calls "standing out from the crowd" — is most important for adolescents, she says.

"The attractive do have a GPA advantage (over) the average," Gordon says.

Researchers analyzed data from the National Longitudinal Study of Adolescent Health, a nationally representative sample of adolescents that launched during the 1994-95 school year and has followed individuals periodically into their 20s and 30s. Interviewers conducting the survey rated students' attractiveness; the researchers obtained data on grade point averages for the analysis, Gordon says. Findings appear in Physical Attractiveness and the Accumulation of Social and Human Capital in Adolescence and Young Adulthood, which will be published online Friday.

Earlier research has shown that better-looking adults earn higher wages overall. The advantage often stems from adolescence, when the better-looking get better grades and are more likely to attain a college degree, setting them on a path for economic advantages as well, she says.

But these advantages differ for men and women, says Caroline Heldman, an associate professor of politics at Occidental College in Los Angeles who studies gender issues and is familiar with the study.

"I'm making the argument that it doesn't work the same way for women. We live in a beauty culture that values us for our attractiveness," she says. "Living in a culture where we value looks harms women.

"Attractive women will get a benefit overall in occupations, but when you're talking about leadership positions, being sexually attractive actually works against you," Heldman adds.

The new study does find some disadvantages associated with being attractive, such as being more likely to date, have sexual partners and drink heavily, which Gordon says could have a negative impact on grades and college performance.

Those rated below average in looks in high school didn't suffer an overall disadvantage in terms of grades, compared with their average-looking peers. But the analysis notes that those rated by others as "being on the ugly side of looks" are more depressed and have fewer friends than those average in looks, both in high school and young adulthood.

And, when it comes to grades, what about teacher bias toward better-looking kids?

Gordon says researchers controlled for the things they could, including age, gender, race/ethnicity, family income, parents' marital status and parental education, as well as the students' grade in high school, course selections and a standardized measure of their vocabulary. But she says they couldn't directly measure whether teachers gave better grades to better-looking students.

Gordon says this study is important because most research on looks has focused on elementary school kids or adult earners.

"We did want to highlight the importance of looking at physical attractiveness in high school and adolescents, given that it's been looked at so little in academic literature," she says. "We may be able to help teachers and students get past the way looks affect those initial impressions."